Is Your Pool Losing Pressure? Here’s How to Spot It and Fix It Fast

Is your pool water looking a little murky? Are the jets not as strong as they used to be? If so, you might be dealing with a pool pressure issue. But don’t worry—we’re here to help you figure out what’s going on and how to get your pool back to its sparkling, clear water in no time.

How to tell if you’ve got a pressure problem

Let’s start with a quick check: are the return jets (those little water outlets on your pool walls) feeling weaker than usual? That’s often the first sign that your pool’s pressure is off.

What could be causing pressure problems in your pool?

Several factors can cause pressure issues in your pool. Your best diagnostic tool is the pressure gauge. This small round dial with a needle shows whether water is properly circulating through the filter. It displays the water pressure in PSI or bar.

Pro Tip: To determine your pool’s normal pressure, make sure your filtration system is clean (either a clean sand bed, a brand-new cartridge, or one that’s just been thoroughly cleaned). Then, take note of the pressure gauge reading—this is your reference pressure.

There are two possible areas where the problem could lie: either after the pump or before it.

High Pressure (the needle is higher than normal)? The issue is likely after the pump, meaning water is having trouble getting out. Possible culprits:

• A dirty or clogged cartridge filter
• Sand clogged with debris
• A closed valve
• A return plug that didn’t get removed when you opened the pool for the season

Low Pressure (the needle is lower than usual)? Then the issue is probably before the pump, meaning it’s struggling to pull water in. Possible causes:

• Leaves covering the main drain (check if it’s still pulling water)
• Debris in the skimmer or pump baskets
• Gunk stuck in the motor’s impeller
• A closed valve
• A leak in the suction line

If your pressure gauge reads zero:
This means it’s no longer working. While it doesn’t cause pressure problems, it also won’t help you detect them. Try tapping it lightly or turning the pump off and on again. If it stays at zero, it needs to be replaced.

How to fix the pressure problem

If your pressure is too high:

• Double-check that you removed the return plug.
• Got a sand filter? Give it a good backwash and clean the sand with the right product. Still too high? It might be time to change the sand.
• Using a cartridge filter? Clean it with a proper filter cleaner. If it’s still struggling, consider replacing the cartridge.
• Make sure all your valves are fully open and nothing is restricting water flow.

If your pressure is too low:

• Check your pool’s water level—it should be halfway up the skimmer opening.
• Make sure there’s no air in the pump and that it’s primed (some pumps need to be filled with water before starting).
• Clean out the skimmer and pump baskets—leaves and debris are common culprits.
• If the bottom drain is covered in leaves, switch to skimmer-only circulation for now.
• Tighten up the pump lid and fittings to rule out air leaks.
• Confirm your 3-way valve is open and allowing water to reach the pump.

Have questions? Contact your Sima expert today!